In The Borgias-fandom, there’s a lot of talk about ratings and how people must watch the show as it airs, in order to give the show better ratings.
That’s not how this works! Unless you have a device registering your tv habits, there’s no way for anyone to know what you’re watching!
However, if you’re watching the show online, legally, (if that’s possible), they might be able to tell how many people are watching at each moment. But otherwise, they’d have to either ask you if you watched, or have installed something (like a Nielsen device in the US) in your home for it to be noticed. All ratings are just based on a limited amount of statistical data from a fairly small sample.
So, you should tell all the people with Nielsen devices (and the like) to watch the show, and, more importantly, tell all the people who don’t have Showtime, but are watching anyway, to start paying for the show. (And then buy the DVDs!)
The more people who pay to watch it legally, the more likely a season 4 is! Showtime lives off its subscribers, after all.
(Didn’t Francois Arnaud say, in one of his first interviews on the set of The Borgias, that getting the part, meant it’d be four years of his life? Makes me think they’ve planned for at least four seasons from the beginning and barring any catastrophes, that’s what we’ll get.)